FYI: The ecological role of pike [Archive] - Fly Fishing Forum

: FYI: The ecological role of pike


Dble Haul
02-16-2006, 11:15 AM
I found this brief summary by Leon Roskilly to be succinct and topical. It's his views on the ecological role of pike....

Summary

Pike have existed, largely unchanged, for millions of years. They have evolved strategies for living in balance with their prey.

Nature maintains a natural balance of around 10% pike, organised into a pyramid hierarchy. Should the balance be disturbed, nature will fight to restore the natural balance, to the detriment of the fishery.

Pike will help to maintain the health of a fishery by eliminating diseased and dead fish.

Pike-free waters may end up full of stunted and diseased fish, prone to fish kills in hot weather.

Pike will keep insect-eating fish numbers down to safe levels, thus avoiding the disaster of eutrophication when excessive phytoplankton growth leads to water pollution and fish deaths.

Moving pike unbalances two waters, instead of just one, has a risk of transferring disease and parasites, and probably results in the lingering death of most relocated fish anyway.

Pike fishing can bring in additional revenues to trout only fisheries, and provide more varied sport for today’s fly fishing enthusiasts.

Pike mop up a proportion of winterkill fish.

teflon_jones
02-16-2006, 12:42 PM
Thanks for the summary Mark. I'd like to hear the other side of the coin though (everything has one :) ). What are the negatives to adding pike to a fishery? It can't all be good news. One thing that comes to mind is if there's not enough unhealthy fish for the pike, can they kill off the healthy fish and ruin a fishery? Or will they keep themselves in check by taking away their own food source?

I've often wondered about this because there's a lot of fisheries in MA that have overpopulations of panfish/perch and the problem is only getting worse. Could pike solve these problems? Can pike even survive in these environments, or is there a specific set of environmental factors they need to sustain a population in a body of water? So many questions, so few answers (so far)...

Dble Haul
02-16-2006, 01:11 PM
Thanks for the summary Mark. I'd like to hear the other side of the coin though (everything has one :) ). What are the negatives to adding pike to a fishery? It can't all be good news.

Well, there's this point mentioned in the summary:


"Moving pike unbalances two waters, instead of just one, has a risk of transferring disease and parasites, and probably results in the lingering death of most relocated fish anyway."

There are far too many variables for non-professionals to play bucket biology. The summary stresses how important pike are to their native waters, and warns of introduction to other waters without the consultation of experts. The results could be exactly what you're describing and asking about in the second half of your post.

Sean Juan
02-16-2006, 02:16 PM
Hey Teflon,

The Mass Dept of fisheries website tells the location of where pike were introduced into a few Mass "Lakes". Seems introducing Pike was a big deal about 15 years ago.

Not sure how successful the program was if at all - most places known for their Pike fishing either already had them or are largish river systems. The few on the list that I have fished contained mostly stunted calico bass and yellow perch.

Bob Pauli
02-16-2006, 02:50 PM
Ask any California fisher about the "benefits" of pike in Lake Davis.

Dble Haul
02-16-2006, 02:53 PM
Details on that?

Adrian
02-16-2006, 03:55 PM
When thinking about introducing a species to a water where it didn't exist before, at least in recorded fact, its probably worth asking why the species isn't there today. If the conditions are "right", and of course that is an aweful lot of "IFs", things will establish naturally (i.e. without interference from man) into some sort of balance.

I know little about Pike but from what I understand they have very particular breeding requirements that includes seasonal flooding of marshland.

It would be interesting to know how long it takes a fish population to naturally become established in a man-made water. The sequence in which different species become established, how long before the predators turn up etc.

I wonder if there are any longitudinal studies out there?

flyjkol
02-16-2006, 04:44 PM
Ask any California fisher about the "benefits" of pike in Lake Davis.

Correct me if I'm wrong, but I think Lake Davis was a fishery with a tremendous trout fishery until the introduction of pike. The problem has gotten so bad that the state recommends that any pike caught should be killed.

Dble Haul
02-16-2006, 04:50 PM
If that's the case, then I wonder how they got there in the first place. Was it a planned stocking or illegal transplanting of the pike? If it was a planned stocking, that shows that even carefully laid plans can go awry when mother nature is circumvented. When pike take hold in a body of water, it doesn't take long for them to get a firm grip.

s2ary
02-17-2006, 06:54 AM
From what I understand Tiger Muskies are a much better option for restructuring fish biomass in lakes that lack apex predators.

One of the main reasons is that they are a sterile hybrid that can tolerate warm temperatures.

There are a lot of myths when it comes to Essox introductions. The biggest one is that they will ruin the fishery or that they eat all the trout. That is simply not true.

Adam
02-18-2006, 07:00 AM
Before moving to SE FL, I did a lot of pickerel (smaller cousins to the pike) fishing in my NJ lakes. I really loved fishing for them with top water stuff; their surface attacks can be stunning. Anyway, in the lakes I fished, it appeared that the pickerel didn't do anything to the bass/carp/crapie/blue gill population. They were all there, although they may have hung out in different areas. Anyway, after doing pickerel, as much as I hate cold weather, I decided to go after trophy pike in northern Manitoba. Know great skill level there, but great action fishing, nonetheless.

Interestingly, the lake I fished in only held northern pike and walleye, no trout at all. Whereas, many of the other nearby lakes held these two species and various trout. Why? IMHO, it was due to the depths of the lakes. My trophy lake, and indeed, many trophy pike were to be had on the fly, was generally a much shallower lake that the multi-specie lakes. So, all things being equal, could it be the depths of the lakes that have something to do with pike not wiping out other species?

teflon_jones
02-18-2006, 10:43 AM
I don't know why I didn't remember this when I originally posted, but the introduction of pike has devastated some of the salmon fisheries in Maine. The salmon don't really have much protection from the pike because they're not really scaly I guess.

juro
02-18-2006, 11:03 AM
The key word in these posts is "introduction".

Don't blame the pike for our screw-ups.

CascoBay
02-18-2006, 12:32 PM
Doublehaul makes a great point about Pike sustaining the balance of a fishery. The example I would offer up is Labrador, the huge brook trout are a result of selective "herd" trimming by the northern pike of those waters. In Maine, we have a few scenarios: First, is the Belgrade lakes region where pike were introduced, which in turn greatly hurt a good landlocked salmon population. However, the pike have been embraced in the region, and offer a great economic boost via the fishery. On the other hand, Sebago lake, Maine's true last southern stand for Landlocked Salmon experienced an illegal stocking recently. A northern Pike was pulled from the waters during an electroshock study by state fisheries biologists. We are still waiting to find out the long term effects.
The introduction of any species into an enviroment can produce detramental effects, this is clearly evident in the case of illegal stockings throughout the states.

s2ary
02-18-2006, 07:39 PM
Chances are the northern lakes that are lacking salmoniods are shallow and have low to moderate oxygen levels during late winter. The other thing is that they could also have populations of rough fish like suckers and chubs.

Another truth in the matter is that essox are cool water fish and salmonoids are cold water fish so their niches only overlap periodically during the winter and the early spring. However the coldwater fish are only mildly at risk during these times because the pike are active but are strictly opportunistic feeders and have slower more vulnerable prey that they are more likely to feed on.

In actuality salmoniods are more at risk from barred and spotted muskies that suspend in deep water during the summer, but these fish are seeking easy pelagic species and not land locks so the risk is low.

The main thing to remember about these situations are that the fish biomass will reach a new dynamic equilibrium and in some peoples minds “there’s a lot less salmon here than before.” The reality is that the salmon populations are held in place artificially in the first place, and now they are competing for bait.

In Maine, Landlocks only naturally occurred in 6-7 lakes. All the other LL fisheries were introduced at the expense of the once fabulous Brook Trout fisheries. Along with the LLs, Rainbow smelt were also introduced to feed the salmon. That one two punch is devastating on the existing species, but now that the salmon are not the only predator with a high metabolism in the spring, they are forced to compete with the pike for the smelt.

The better question is; has the pike introduction (albeit illegal and thus a bad thing) negatively impacted the fishery or has the introduction realigned the fish biomass making a stronger more balance system. It would seem the answer falls in if you are a fisherman or if you enjoy trolling all summer for LLs.

Dble Haul
02-20-2006, 01:32 PM
The key word in these posts is "introduction".

Don't blame the pike for our screw-ups.

Exactly.

As for an earlier post stating that pickeral had little or no impact on the stunted populations of panfish in a particular body of water, I'm not surprised. Pickeral are insect and tiny fish eaters until they are about six inches long, and even when they get to be three or four pounds they tend to feed on smaller soft rayed baitfish and amphibians instead of perch, sunfish, and other spiny rayed panfish. Only truly large pickeral will eat them, but even a small twenty inch pike will do the same.